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      <td width="400px"><p class="toc level1"><a href="docinfo.html">Document Information</a></p>
<p class="toc level1 tocsp"><a href="gexaf.html">Preface</a></p>
<p class="toc level1 tocsp"><a href="gfirp.html">Part&nbsp;I&nbsp;Introduction</a></p>
<p class="toc level2"><a href="bnaaw.html">1.&nbsp;&nbsp;Overview</a></p>
<p class="toc level2"><a href="gfiud.html">2.&nbsp;&nbsp;Using the Tutorial Examples</a></p>
<p class="toc level1 tocsp"><a href="bnadp.html">Part&nbsp;II&nbsp;The Web Tier</a></p>
<p class="toc level2"><a href="bnadr.html">3.&nbsp;&nbsp;Getting Started with Web Applications</a></p>
<p class="toc level2"><a href="bnaph.html">4.&nbsp;&nbsp;JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="giepx.html">5.&nbsp;&nbsp;Introduction to Facelets</a></p>
<p class="toc level2"><a href="gjddd.html">6.&nbsp;&nbsp;Expression Language</a></p>
<p class="toc level2"><a href="bnaqz.html">7.&nbsp;&nbsp;Using JavaServer Faces Technology in Web Pages</a></p>
<p class="toc level2"><a href="gjcut.html">8.&nbsp;&nbsp;Using Converters, Listeners, and Validators</a></p>
<p class="toc level2"><a href="bnatx.html">9.&nbsp;&nbsp;Developing with JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="gkmaa.html">10.&nbsp;&nbsp;JavaServer Faces Technology Advanced Concepts</a></p>
<p class="toc level2"><a href="bnawo.html">11.&nbsp;&nbsp;Configuring JavaServer Faces Applications</a></p>
<p class="toc level2"><a href="gkiow.html">12.&nbsp;&nbsp;Using Ajax with JavaServer Faces Technology</a></p>
<p class="toc level2"><a href="gkhxa.html">13.&nbsp;&nbsp;Advanced Composite Components</a></p>
<p class="toc level2"><a href="bnavg.html">14.&nbsp;&nbsp;Creating Custom UI Components</a></p>
<p class="toc level2"><a href="bnafd.html">15.&nbsp;&nbsp;Java Servlet Technology</a></p>
<p class="toc level2"><a href="bnaxu.html">16.&nbsp;&nbsp;Internationalizing and Localizing Web Applications</a></p>
<p class="toc level3"><a href="bnaxv.html">Java Platform Localization Classes</a></p>
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<p class="toc level3"><a href="">Providing Localized Messages and Labels</a></p>
<p class="toc level4"><a href="#gkuia">Establishing the Locale</a></p>
<p class="toc level4"><a href="#bnaxy">Setting the Resource Bundle</a></p>
<p class="toc level4"><a href="#gkufc">Retrieving Localized Messages</a></p>
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<p class="toc level3 tocsp"><a href="bnaya.html">Date and Number Formatting</a></p>
<p class="toc level3"><a href="bnayb.html">Character Sets and Encodings</a></p>
<p class="toc level4"><a href="bnayb.html#bnayc">Character Sets</a></p>
<p class="toc level4"><a href="bnayb.html#bnayd">Character Encoding</a></p>
<p class="toc level1 tocsp"><a href="bnayk.html">Part&nbsp;III&nbsp;Web Services</a></p>
<p class="toc level2"><a href="gijti.html">17.&nbsp;&nbsp;Introduction to Web Services</a></p>
<p class="toc level2"><a href="bnayl.html">18.&nbsp;&nbsp;Building Web Services with JAX-WS</a></p>
<p class="toc level2"><a href="giepu.html">19.&nbsp;&nbsp;Building RESTful Web Services with JAX-RS</a></p>
<p class="toc level2"><a href="gjjxe.html">20.&nbsp;&nbsp;Advanced JAX-RS Features</a></p>
<p class="toc level2"><a href="gkojl.html">21.&nbsp;&nbsp;Running the Advanced JAX-RS Example Application</a></p>
<p class="toc level1 tocsp"><a href="bnblr.html">Part&nbsp;IV&nbsp;Enterprise Beans</a></p>
<p class="toc level2"><a href="gijsz.html">22.&nbsp;&nbsp;Enterprise Beans</a></p>
<p class="toc level2"><a href="gijre.html">23.&nbsp;&nbsp;Getting Started with Enterprise Beans</a></p>
<p class="toc level2"><a href="gijrb.html">24.&nbsp;&nbsp;Running the Enterprise Bean Examples</a></p>
<p class="toc level2"><a href="bnbpk.html">25.&nbsp;&nbsp;A Message-Driven Bean Example</a></p>
<p class="toc level2"><a href="gkcqz.html">26.&nbsp;&nbsp;Using the Embedded Enterprise Bean Container</a></p>
<p class="toc level2"><a href="gkidz.html">27.&nbsp;&nbsp;Using Asynchronous Method Invocation in Session Beans</a></p>
<p class="toc level1 tocsp"><a href="gjbnr.html">Part&nbsp;V&nbsp;Contexts and Dependency Injection for the Java EE Platform</a></p>
<p class="toc level2"><a href="giwhb.html">28.&nbsp;&nbsp;Introduction to Contexts and Dependency Injection for the Java EE Platform</a></p>
<p class="toc level2"><a href="gjbls.html">29.&nbsp;&nbsp;Running the Basic Contexts and Dependency Injection Examples</a></p>
<p class="toc level2"><a href="gjehi.html">30.&nbsp;&nbsp;Contexts and Dependency Injection for the Java EE Platform: Advanced Topics</a></p>
<p class="toc level2"><a href="gkhre.html">31.&nbsp;&nbsp;Running the Advanced Contexts and Dependency Injection Examples</a></p>
<p class="toc level1 tocsp"><a href="bnbpy.html">Part&nbsp;VI&nbsp;Persistence</a></p>
<p class="toc level2"><a href="bnbpz.html">32.&nbsp;&nbsp;Introduction to the Java Persistence API</a></p>
<p class="toc level2"><a href="gijst.html">33.&nbsp;&nbsp;Running the Persistence Examples</a></p>
<p class="toc level2"><a href="bnbtg.html">34.&nbsp;&nbsp;The Java Persistence Query Language</a></p>
<p class="toc level2"><a href="gjitv.html">35.&nbsp;&nbsp;Using the Criteria API to Create Queries</a></p>
<p class="toc level2"><a href="gkjiq.html">36.&nbsp;&nbsp;Creating and Using String-Based Criteria Queries</a></p>
<p class="toc level2"><a href="gkjjf.html">37.&nbsp;&nbsp;Controlling Concurrent Access to Entity Data with Locking</a></p>
<p class="toc level2"><a href="gkjia.html">38.&nbsp;&nbsp;Improving the Performance of Java Persistence API Applications By Setting a Second-Level Cache</a></p>
<p class="toc level1 tocsp"><a href="gijrp.html">Part&nbsp;VII&nbsp;Security</a></p>
<p class="toc level2"><a href="bnbwj.html">39.&nbsp;&nbsp;Introduction to Security in the Java EE Platform</a></p>
<p class="toc level2"><a href="bncas.html">40.&nbsp;&nbsp;Getting Started Securing Web Applications</a></p>
<p class="toc level2"><a href="bnbyk.html">41.&nbsp;&nbsp;Getting Started Securing Enterprise Applications</a></p>
<p class="toc level1 tocsp"><a href="gijue.html">Part&nbsp;VIII&nbsp;Java EE Supporting Technologies</a></p>
<p class="toc level2"><a href="gijto.html">42.&nbsp;&nbsp;Introduction to Java EE Supporting Technologies</a></p>
<p class="toc level2"><a href="bncih.html">43.&nbsp;&nbsp;Transactions</a></p>
<p class="toc level2"><a href="bncjh.html">44.&nbsp;&nbsp;Resource Connections</a></p>
<p class="toc level2"><a href="bncdq.html">45.&nbsp;&nbsp;Java Message Service Concepts</a></p>
<p class="toc level2"><a href="bncgv.html">46.&nbsp;&nbsp;Java Message Service Examples</a></p>
<p class="toc level2"><a href="gkahp.html">47.&nbsp;&nbsp;Advanced Bean Validation Concepts and Examples</a></p>
<p class="toc level2"><a href="gkeed.html">48.&nbsp;&nbsp;Using Java EE Interceptors</a></p>
<p class="toc level1 tocsp"><a href="gkgjw.html">Part&nbsp;IX&nbsp;Case Studies</a></p>
<p class="toc level2"><a href="gkaee.html">49.&nbsp;&nbsp;Duke's Tutoring Case Study Example</a></p>
<p class="toc level1 tocsp"><a href="idx-1.html">Index</a></p>
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<a name="bnaxw"></a><h2>Providing Localized Messages and Labels</h2>
<p><a name="indexterm-1165"></a>Messages and labels should be tailored according to the conventions of a user&rsquo;s
language and region. There are two approaches to providing localized messages and labels
in a web application:</p>


<ul><li><p>Provide a version of the web page in each of the target locales and have a controller servlet dispatch the request to the appropriate page depending on the requested locale. This approach is useful if large amounts of data on a page or an entire web application need to be internationalized.</p>

</li>
<li><p>Isolate any locale-sensitive data on a page into resource bundles, and access the data so that the corresponding translated message is fetched automatically and inserted into the page. Thus, instead of creating strings directly in your code, you create a resource bundle that contains translations and read the translations from that bundle using the corresponding key.</p>

</li></ul>
<p>The Duke&rsquo;s Tutoring application follows the second approach. Here are a few lines
from the default resource bundle <tt>messages</tt>.<tt>properties</tt>:</p>

<pre>nav.main=Main page
nav.status=View status
nav.current_session=View current tutoring session
nav.park=View students at the park
nav.admin=Administration

admin.nav.main=Administration main page
admin.nav.create_student=Create new student
admin.nav.edit_student=Edit student
admin.nav.create_guardian=Create new guardian
admin.nav.edit_guardian=Edit guardian
admin.nav.create_address=Create new address
admin.nav.edit_address=Edit address
admin.nav.activate_student=Activate student</pre>

<a name="gkuia"></a><h3>Establishing the Locale</h3>
<p><a name="indexterm-1166"></a><a name="indexterm-1167"></a>To get the correct strings for a given user, a web application either
retrieves the locale (set by a browser language preference) from the request using
the <tt>getLocale</tt> method, or allows the user to explicitly select the locale.</p>

<p>A component can explicitly set the locale by using the <tt>fmt:setLocale</tt> tag.</p>

<p>The <tt>locale-config</tt> element in the configuration file registers the default locale and also
registers other supported locales. This element in Duke's Tutoring registers English as the
default locale and indicates that German, Spanish, Portuguese, and Chinese are supported locales.</p>

<pre>&lt;locale-config&gt;
    &lt;default-locale&gt;en&lt;/default-locale&gt;
    &lt;supported-locale&gt;de&lt;/supported-locale&gt;
    &lt;supported-locale&gt;es&lt;/supported-locale&gt;
    &lt;supported-locale&gt;pt&lt;/supported-locale&gt;
    &lt;supported-locale&gt;zh&lt;/supported-locale&gt;
&lt;/locale-config&gt;</pre><p>The Status Manager in the Duke&rsquo;s Tutoring application uses the <tt>getLocale</tt> method
to retrieve the locale and a <tt>toString</tt> method to return a localized translation
of a student's status based on the locale.</p>

<pre>public class StatusManager {
    
    private FacesContext ctx = FacesContext.getCurrentInstance();
    private Locale locale;

    /** Creates a new instance of StatusManager */
    public StatusManager() {
        locale = ctx.getViewRoot().getLocale();
    }
    
    public String getLocalizedStatus(StatusType status) {
        return status.toString(locale);
    }

}</pre>

<a name="bnaxy"></a><h3>Setting the Resource Bundle</h3>
<p>The resource bundle is set with the <tt>resource-bundle</tt> element in the configuration file.
The setting for Duke's Tutoring looks like this:</p>

<pre>&lt;resource-bundle&gt;
    &lt;base-name&gt;dukestutoring.web.messages.Messages&lt;/base-name&gt;
    &lt;var&gt;bundle&lt;/var&gt;
&lt;/resource-bundle&gt;</pre><p><a name="indexterm-1168"></a>After the locale is set, the controller of a web application could retrieve
the resource bundle for that locale and save it as a session attribute
(see <a href="bnagm.html#bnago">Associating Objects with a Session</a>) for use by other components or simply be used to return
a text string appropriate for the selected locale:</p>

<pre>public String toString(Locale locale) {
    ResourceBundle res = 
        ResourceBundle.getBundle("dukestutoring.web.messages.Messages", locale);
    return res.getString(name() + ".string");
}</pre><p>Alternatively, an application could use the <tt>f:loadBundle</tt> tag to set the resource bundle.
This tag loads the correct resource bundle according to the locale stored in
<tt>FacesContext</tt>.</p>

<pre>&lt;f:loadBundle basename="dukestutoring.web.messages.Messages"
    var="bundle"/></pre><p>Resource bundles containing messages that are explicitly referenced from a JavaServer Faces tag
attribute using a value expression must be registered using the <tt>resource-bundle</tt> element of
the configuration file.</p>

<p>For more information on using this element, see <a href="bnaxc.html">Registering Custom Localized Static Text</a>.</p>



<a name="gkufc"></a><h3>Retrieving Localized Messages</h3>
<p><a name="indexterm-1169"></a>A web component written in the Java programming language retrieves the resource bundle
from the session:</p>

<pre>ResourceBundle messages = (ResourceBundle)session.getAttribute("messages");</pre><p>Then it looks up the string associated with the key <tt>person.lastName</tt> as
follows:</p>

<pre>messages.getString("person.lastName");</pre><p>You can only use a <tt>message</tt> or <tt>messages</tt> tag to display messages that
are queued onto a component as a result of a converter or validator
being registered on the component. The following example shows a <tt>message</tt> tag that
displays the error message queued on the <tt>userNo</tt> input component if the validator
registered on the component fails to validate the value the user enters into
the component.</p>

<pre>&lt;h:inputText id="userNo" value="#{UserNumberBean.userNumber}">
    &lt;f:validateLongRange minimum="0" maximum="10" />
     ...
&lt;h:message
     style="color: red;
     text-decoration: overline" id="errors1" for="userNo"/></pre><p>For more information on using the <tt>message</tt> or <tt>messages</tt> tags, see <a href="bnarf.html#bnaso">Displaying Error Messages with the <tt>h:message</tt> and <tt>h:messages</tt> Tags</a>.</p>

<p>Messages that are not queued on a component and are therefore not
loaded automatically are referenced using a value expression. You can reference a localized message
from almost any JavaServer Faces tag attribute.</p>

<p>The value expression that references a message has the same notation whether you
loaded the resource bundle with the <tt>loadBundle</tt> tag or registered it with the
<tt>resource-bundle</tt> element in the configuration file.</p>

<p><a name="indexterm-1170"></a><a name="indexterm-1171"></a>The value expression notation is <tt>var.message</tt>, in which <tt>var</tt> matches the <tt>var</tt> attribute of
the <tt>loadBundle</tt> tag or the <tt>var</tt> element defined in the <tt>resource-bundle</tt> element of
the configuration file, and <tt>message</tt> matches the key of the message contained in the
resource bundle, referred to by the <tt>var</tt> attribute.</p>

<p>Here is an example from <tt>editAddress.xhtml</tt> in Duke's Tutoring:</p>

<pre>&lt;h:outputLabel for="country" value="#{bundle['address.country']}:" /&gt;</pre><p>Notice that <tt>bundle</tt> matches the <tt>var</tt> element from the configuration file and that
<tt>country</tt> matches the key in the resource bundle.</p>

<p>For information on using localized messages in JavaServer Faces applications, see <a href="bnarf.html#bnasi">Displaying Components for Selecting Multiple Values</a>.</p>


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